Ok, as a non-native English speaker, I had to google that abom-word-thingy
Question; How would the "rearranged" keyboard be "bad/ugly" for me as I do not have any whatsoever experience with the original 41 and/or the landscape series?
All my calcs (exept the not-used non-rpn CC sized cheapo) are portrait and, based on my, not explainable, disliking of a landscape calc, why would I find the keyboard rearranged layout not good?

Question; How would the "rearranged" keyboard be "bad/ugly" for me as I do not have any whatsoever experience with the original 41 and/or the landscape series?
All my calcs (exept the not-used non-rpn CC sized cheapo) are portrait and, based on my, not explainable, disliking of a landscape calc, why would I find the keyboard rearranged layout not good?

Not being exposed to a true 41 could be indeed an advantage but, just to name one thing: try to use those arithmetic operator keys in the middle of the keyboard.

As a RPN nerd I frequently look in the internet if HP brings out new RPN calculators. Googleing for RPN some time ago I saw these SM CC calculators. Nice but it didn't feed my needs (and wants). Finally I found out that SM also offers the L-types - BINGO!

for a longer time I was searching for a good and programmable calculator for my Android tablet. After trying quite a few emulators, which either
does not use the space on the screen very well (my tablet is a 7" one) or need to have the original calculator for legally owning a ROM image or
simply were better in design than usability I first came across the HP42s-page on wikipedia, which states something like "best calculator ever made".
Then -- via a wikpedia link list -- I found Thomas OpenSourced (YEAH!), free (YEAH!) and independently implemented (YEAH!) Free42, which solves
all my previous "problems" in one go. Together with the manual for the HP42s this was EXACTLY for what I have searched for.

Then -- I think it was while I am was surfing the net for HP42s programs I found that at HPmuseum.org -- a posting, that Michael and David were
prototyping a DM42L (the landscape version).

From then on I was checking for news around the DM42 regularly and in the moment the DM42L was changed for a DM42 (portrait version) the
DM42 mutated from a "oh,intersting" to a "I must have that"-item.

I owned a RPN-calculator never before and only one programmable calculator (Casio FX602P) in total. But I know "kinda RPN" for playing around with LISP and RACKET.

I think RPN as a notation system has a comparable reputation as the vi/vim editor: As long as you don't have touched them you remain a victim of what other say about them: old-fashioned, old-school, steep learning curve, awkward and somehow quirky.

As soon you learned them you start to love them and finally you are thinking: "What the hell I did all the years before?"

Yep! When I decided to get the DM15L, I looked at the DM42, but decided the DM15L would do the trick. Once I had the DM15L in my hands I couldn't resist ordering a DM42. I'm guessing that may not be the end of it!

These calculators make me think of the first one I ever used. I remember my Dad taking us kids on a trip to the city to buy a Sharp EL-8. I remember learning the multiplication table on it.

I'm not sure how I learnt about Swiss Micros, but I was always looking at stuff around the HP-41CV online (before I sold it to fund the purchase of a DM-15L).

Although I have a (twenty year old) Computer Science degree my maths is pretty poor, and it was only an intensive month of study (holiday from work) that I managed to get to grips with the basics of Algebra and Trigonometry (with help from an HP-35S). I am now moving onto Vectors and Complex Numbers and Matrices, and purchased the DM-15L to assist with some heavy number crunching as the HP-35S is (from what I have read) lacking in those areas. Also the HP-35S font is appalling, very hard to read. It's not a bad calculator though but I wish the display was better.

My work involves ARM low-level stuff and I use an HP16C quite a bit (and also own a DM-16L and DM-16 as I wanted everything in that range!) and it was in fact the quality of the DM-16L that made me go out and purchased the DM-15L. I thought... heck the 15L would besuperb for my maths courses...

I am very happy with my Swiss Micros devices... they are superbly made... feel much more solid (to me) than the Voyagers and the font (in block font) is superb, sharp and very very easy to read, better than any calculator I have ever previously used.

The only thing I miss moving from the HP-35S to DM-15L is obviously seeing the y register, but it hasn't really made much difference in practice and I guess once your RPN gets to a certain level you really don't need to see it anymore.